Turkey's interior ministry has opened an investigation into Ghosn's apparent transfer between private jets at an Istanbul (pictured) airport on Monday. Officials questioned seven people, including four pilots, as part of the probe, news agency DHA reported Thursday. The investigation is focused on two flights. The first, a Bombardier labelled TC-TSR, flew from Osaka in Japan, landed in Istanbul at 5:15 am and parked in a hangar. The second was a private jet to Beirut, a Bombardier Challenger 300 TC-RZA, which left 45 minutes later, according to DHA. Ghosn said in a statement on Thursday that he acted alone without his family's help. The Wall Street Journal reported that he was assisted by a former US special forces operative, Michael Taylor, now working as a private security contractor, who it described as an "expert in the art of clandestine getaways." According to the Journal, the Turkish investigation showed that Taylor and another man had travelled from Dubai to Osaka aboard a private jet on Saturday, a day before Ghosn made his escape, and that the pair were travelling with two large black cases.